1. Field of the Invention
This invention relates generally to crowd control devices and particularly to devices for use by law enforcement and military forces during civil disturbances to control unruly crowds of people without causing serious injury. Still more particularly, this invention relates to a device that uses sonic and light beams to control human behavior.
2. Description of the Prior Art
A large variety of less-than-lethal systems and devices are currently available for employment by law enforcement and military forces in civil disturbances. Riot batons, rubberized metal pellets, chemical agents, water, foam and firearms represent crude and visually offensive technologies intended to minimize serious injury and death during civil unrest. Unfortunately, technologies and their employment suffer weaknesses that often defeat the purpose of avoiding violent escalation. Many are unable to selectively hold a mob at bay, in essence, outside of rock and Molotov cocktail throwing range. Once a mob is able to assault forces with hand thrown projectiles, the employment of deadly force becomes more probable because forces are directly threatened. Many methods are logistically impractical (high pressure water, foam, etc.), which limits their application. Other methods, such as gas, are indiscriminate in their effects, endangering both non-combatants and friendly forces during engagements. Kinetic projectile firing devices (bean bag rounds, rubber bullets, etc.) can, in many instances, maim or kill their targets in contradiction to their purpose. Finally, the employment of such systems is visually offensive from a media or neutral observer standpoint, often resulting in severe harm to law enforcement and military missions due to political disenchantment.
This invention is a portable, combined arms, audio-visual system intended for humane deterrence, riot control and the defusing of possible escalation of civil violence. The audio sub-system generates a directional acoustic beam by means of a linear arrangement of piezoelectric transducers, which are phased to produce directionality and power in the forward direction. The longitudinal end-fired-array is contained within an insulated and internally reflective tube to employ resonance to increase sound pressure levels, while protecting the operator and his team-mates from effects. The intended effect of the acoustic energy is to produce aural pain in an adversary sufficient to deter or prevent a continuation of threatening behavior. The audio sub-system can be operated in a large variety of modes, including the enhancement of a single frequency by phasing, a combination of beat frequencies by separate control of two oscillators, a shift in frequency operation, or a randomized, intermittent operation.
The audio sub-system operates in combination with a pulsed, diffusive laser or flash device. The integration of any one of many off-the shelf, eye-safe, pulsed dazzle-producing light systems accomplishes the unique combined arms concept. While such lasers have been separately developed and patented, this invention uniquely integrates them with acoustic effects, with the intent of causing an adversary synergistic sensory overload, thereby increasing the deterrent and preventative effects of the combined device. In summary, this system provides synergistic and temporary discomfiture to two senses, discouraging further civil aggression at safe stand-off range. It also possesses rheostatic tunability to vary the severity and range of effects.
The system is light-weight, man-portable and self contained. It can be scaled to various, frequencies, amplitudes and applications. All electronics for audio and laser/flash device operation may be carried in a backpack. Both systems are powered by batteries and low and/or high voltage capacitors for extended independent operations. The system can alternatively be plugged into vehicle or building power sources for uninterrupted operations. The system can also be scaled up in capability and flexibility for employment as a vehicle mounted crew served device of greater effective range.
A crowd dispersion device according to the present invention for influencing human behavior comprises an audio system arranged to produce a sound wave that may be directed to a selected location and a video system arranged to produce a light beam that may be directed to the selected location.
The audio system included in the present invention preferably comprises a frame and an array of sound generators mounted in the frame. The frame preferably is formed generally as a tube having a longitudinal axis, an open end and a closed end with the sound wave being emitted generally parallel to the longitudinal axis of the tube.
The array of sound generators is arranged to produce a plurality of sound waves having amplitudes that positively combine along the axis of the tube. The audio system may comprise a linear array of piezoelectric transducers mounted inside the frame. The audio system may alternatively comprise an array of piezoelectric transducers mounted on the tube and arranged to produce sound waves directed radially inward in the tube.
The audio system may alternatively comprise an array of sirens mounted on the tube and arranged to produce sound waves directed radially inward in the tube.
The video system preferably comprises either a flash tube or a laser.
The crowd dispersion device according to the present invention may further comprise an electrical system that may be controlled by a human operator to cause the light source and the sound cannon to produce a light beam and a sound wave, respectively, that may be directed to the selected location to encourage a person to move away from the selected location.
The crowd dispersion device according to the present invention may further comprise a power source selection switch connected to the electrical system, a first electrical connector arranged for connection between the electrical system and an external electrical power source. A battery may be connected to the power source selection switch such that a human operator may actuate the power source selection switch to control whether the electrical system receives electrical power from the battery or from the external electrical power source.
The device according to the present invention may further comprise a pair of pistol grips mounted to the frame and spaced apart a distance convenient for being grasped by a human operator, a sound cannon trigger mounted to a first one of the pistol grips and a light source trigger mounted to the other of the pistol grips.